Quick-break double-throw switch



A. R. WOOLFOLK, JR. QUICK BREAK DOUBLE THROW .SWITCH.

APPLICATION FILED JULY 10] 1918- Patenfed Dee 13, 1921.

arrow/5y UNITED STATES PATENT OFFICE.

RTHUR R. WOOLFOLK, .13., on NEW YORK, N. Y., ASSIGNOR 'ro sebum 1) COMPANY, or DETROIT,- MICHIGAN, A OORPQRATION or MICHIGAN.

-QUICK-BREAK DOUBLE-THROW SWITCH.

Application filed July 10,

To all whom it may concern;

Be it known that I, ARTHUR R. WooLFoLK, Jr, a citizen'of'the United States, residing in the city, county, and State of New York. have invented certain new and useful Improvements in Quick-Break Double-Throw Switches, of which the following is a full, clear, and concise description thereof.

My invention relates to quick break double throw switches generally. These switches may be of the inclosed type and one ofthe objects of my invention is to provide for improved external operation of said double throw quick break switch;

A further object of this invention is to provide improved means whereby an intermediate or neutral position may be assumed by the switch mechanism.

Other objects of this invention will in part be apparent and in part be further described in the detailed description following.

One of the many possible forms which this invention may take is shown 'in the accompanying drawing, in Which- Figure 1 shows a longitudinal'sectional elevation of the switch mechanism and casing, such section being taken on the, line 11 of Fig. 2; and

Fig. 2.is a plan view of the switch mechanism with the cover of the casing open.

Referring in detailto the figures, it will be seen that the switch is inclosed in a casing 2 which includes the base portion and a hinged cover 3. Such cover has a recessed portion 4 to accommodate certain portions of the switch mechanism. It is to be understood, of course, that this cover may be locked in closed position by means of an apertured tongue 5 which passes through an opening in the cover 3 and is adapted to receive the bail or hook portion of a padlock or other suitable locking means. This metal casing is suitably insulated from the electrical parts of the switch mechanism by means of an insulating base 6 which is securely fastened to the base of the casing 2. Upon this insulating base is mounted a pair of contact members 7 which have pivotally mounted thereon knifeblades 8 which are adapted to be thrown from one extreme position, as shown in the drawings, to the other extreme position in the usual manner of operating a double throw switch. These pivoted knife blades cooperate with stationary contacts 9 and 10 arranged at the extreme Specification of Letters Patent. Patented Dem 13,1921

1918. Serial no. 244,179.

limits of its motion. From these contacts 7, 9 and 10, suitable wires may extend and are adapted to be connected to these contacts by means of the connectors shown at 11. These connectors are of the tubular type having a flattened portion which is screwed to the contacts. These knife blades 8 are operated through the medium of a cross head' 12, which in the example shown, is a metalrod which is suitably insulated from the knife blades by means of an insulating sleeve 13. These knife blades are fastened to this insulating sleeve 13 by means of clamping members orf other suitable means, not shown. This cross head 12 has crank members 14 at either end which are pivoted in the sidesof the casing in alinement with the pivots of the knife blades 8. It is, of course, obvious that these crank members 14 may be omitted.

The operating member for this switch mechanism comprises a horizontal portion 15 extending parallel to the horizontal portion of the cross head 12. This horizontal portion continues over and forms crank mem bers 16 which are pivotally mounted in the sides of the casing. From one side an external handle 17 extends by which means this operating member 15 may be externally operated. The means for eonnectingthe cross head 12 and the operating member 15 comprises a slotted spring link, the casing or rigid portion of which is shown at 18. In this link or casing is placed a spring'19 which is fastened to'the operating member 15 and the cross head 12. This link is provided with a slot 20 which allows the operating member to have limited travel within the link. In the position shown in full lines in Fig. 1, the operating member 15 is resting in the lower portion. of the slot 20 and the spring 19 is in contracted position. When this operating member through the medium of the external handle 17 is rocked upwardly, the spring 19 is extended and places stress upon the cross head 12 tending to withdraw the knife blades 8 from engagement with the contacts 9. However, the frictional engagement is suflicient to maintain these two members 8 and 9 in engagement until the operating member 15 strikes against the upper part of the slot 20 and positively initiates the withdrawal of the contacts 8 from engagement with the con- 8 from the contacts 9. The switch mechanism then assumes the position shown in dotted lines, the link being indicated at 18 and the operating member at 15 and the cross head at 12'. In this position the link at its upper end has engaged the cam projection or lug 21. .This serves to temporarilyarrest the motion of the switch in its neutral position. Upon continued motion of the operating member the link is tilted to the position shown at 18 because of the engagement of the cam or lug 21 with its upper portion. This rocks the cross head to the position shown .at 12" and thereafter the link slides free of the cam or lug 21 and the operating member 15 engages the lower portion of the slot and forces the cross head downward and causes the pivoted knife blades 8 to engage the contacts 10. It is, of course, understood that upon reverse operation of the switch the same action takes place as the one just described, as all of the parts are symmetrically arranged W'ithrespectto a vertical central transverse plane. The lug 21 is carried upon an arch shaped member 22 whichmay be ribbed to give added stiffness and may be secured upon the insulating base 6 in the manner shown. This particular arrangement of supporting member for the lug may be'varied, however, within the scope of the invention.

It will be seen from the above. description that a Very simple quick break double throw mechanism has been provided, in which the sole connecting member between the operating member and cross head and knife blades consists of a spring link.

It will be further noted that this spring link controls the motion of the knife blades 8 as may be seen from the dotted illustration in Fig. 1.

It will further be noted that by means of the lug 21 there is a definite stop provided for the neutral position of the switch which would offer a slight resistance to the continued motion of the switch past its neutral position, and would, therefore, be of a decided value when it was intended toopen the switch and leave it in such opened position.

It will further be noted that by means of this invention a quick break double throw switch has been provided which includes a minimum number of parts and that the parts thereof are very substantial and rugged and that the switch will be reliable in its operawith said'link and 'operatin tion and free from complicated constructions.

scription and drawings are to be interpreted in an illustrative sense only, as it is lntended that the invention shall be limited only as defined by the following claims.

I claim:

1. A quick break double throw switch comprising cooperating stationary and movable contacts, a cross head attached to said movable contacts, an operating member, a link intermediate. said operating member. and cross-head, and a cam member for tilting said link.

2. A quick break double throw switch comprising cooperating stationary and movable contacts, a cross head attached to said movable contacts, an operating member, a link intermediate said operating member and cross-head, a cam member for tilting said link, and means for supporting said cam member.

3. A quick break double throw switch comprising cooperating stationary and movable contacts, an operating member, a link intermediate said operating member and movable contacts, and means cooperating with said link and operating member to temporarily arrest the switch in itsneutral position.

4. A quick break double throw switch comprising a base and coiiperating stationary and movable contacts mounted thereon, an'

operating member, a link intermediate said operating member and movable contacts, means incloslng sald operating member and said link in their complete movement from one to the other of their extreme positions, and means associated with said last-mentioned means to temporarily arrest the switch in its neutral position.

5. A quick break double throw switch comprising a base and two pairs of stationary contacts and a cooperating pair of movable contacts, an operating member for said movable contacts, a linkintermediate said op- Itwili be understood that the detailed de-- crating member and said movable contacts.

resilient means associated with said link to obtain a quick break between said pair of movable contacts and said two pairs of stationary contacts, and means cooperating member to temporarily arrest the switch in its neutral position.

ARTHUR a. WOOLFOLK, JR. 

